Preparation of refined bamboo scrimbers with high strength and dimensional stability via saturated steam softening

Bamboo scrimbers are environmentally friendly and sustainable building materials, but their uneven density, poor dimensional stability, and insufficient mechanical strength restrict their application in load-bearing building structures. In this study, refined bamboo scrimbers were fabricated via saturated steam softening. The saturated steam treatment softened cell walls of bamboo by degrading the hemicellulose, decreasing the relative crystallinity and deforming the cell wall structure, which is beneficial for mechanical fluffing to obtain refined bamboo fiber bundles, and hot pressing into dimensionally stable and high-strength refined bamboo scrimbers. The average fiber diameter of refined bamboo fiber bundles was 0.20 mm, representing an 82.14% reduction compared with untreated fibers. Relative to the untreated group, the refined bamboo scrimbers exhibited a marked improvement in performance, with the flexural strength increased by a maximum of 31.37%, the flexural modulus increased by a maximum of 50.34%, the 24-hour WAR rate decreased by a maximum of 46.08%, and the TSR decreased by a maximum of 46.33%. Overall, the refined bamboo scrimber showed remarkable improvements in density uniformity, mechanical strength, and dimensional stability, highlighting its great potential for a wider range of high-performance applications. • Fabricated from refined bamboo bundles via saturated-steam treatment. • Refined bamboo bundles had an average diameter of 0.20 mm with minimal variation. • Density uniformity improved, with 80% reduction of CV vs untreated. • Bamboo scrimber showed high specific strength and dimensional stability.